In the field of large scale production of prepared foods, an ever larger variety of food pieces are machine coated with batter and breading before being fried in deep fat. Many additional processes may be required in the total preparation of the food pieces, but this invention relates solely to breading machines.
Breading is a dry farinaceous material which takes many forms and nearly always includes wheat flour in some form. It may also include other grain flour or meal, seasonings, spices, shortenings, etc. Most breading material may be roughly classified by its appearance into one of three classes; flour breading, free flowing breading, or Japanese style crumbs. Each of these has its own pecularities which affect the design of a machine used for applying the breading to food pieces.
For instance flour breading, which consists of finely ground dust-like particles with the normal appearance of wheat flour, have a tendency to pack under pressure. The packing action can make the breading bridge over openings as large as six inches in minor dimension, which in turn makes it difficult to remove from any type hopper in which the bottom slopes upwards and away from a bottom opening. Flour breadings do not flow freely. There are other pecularities of flour breadings which will become apparent later.
Breadings classified as free flowing are usually cracker meal consisting of reasonably hard and roughly spherical particles ranging in size from dust to about three-thirty seconds of an inch in diameter. Such breadings flow so freely that any containment enclosure must have provision to prevent leakage from any cracks or openings. Even a small hole may drain an entire containment enclosure down to the angle of repose of the breading. There are other pecularities of free flowing breadings which will become apparent later.
Breadings classified as Japanese style crumbs and the pecularities of their use are fully covered in U.S. Pat. No. 4,333,415--Miller-Hummel, and are not relevant to the subject invention.
The history of large scale use of breading machines in the food industry covers only about three decades. In that time period, breading machines have become larger and more complex, they run at higher speeds for longer times, and the proliferation of new food products and breading formulations has required that many variations and special machines be built. All of this, coupled with the high inflation rates of the last ten years and the high interest rates of the last few years, plus the sanitary and safety regulations of various governmental agencies, has made the high cost of a new breading machine more than many processors can afford.
As will be seen later, cost is a primary consideration in this invention, therefore it is relevant to discuss the complexity of two typical breading machines. The first is described and pictured in U.S. Pat. No. 4,128,160 Deal-Morley. In FIGS. 1 and 2 thereof, the hopper 13 may be seen to be composed of at least sixteen separate planar surfaces, many showing complex geometry, and many joinable only by welding. FIGS. 3, 4, 5 thereof show the construction of the fixed half of the vertical screw housing 20, again with many separate surfaces and complex geometry. In addition, FIG. 1 shows that the vertical screw housing 20 must extend from far below the product belt 12 to a point well above the hopper 13. In fact, a vertical screw housing may be over six feet long, which complicates the problem of maintaining relative dimensions with other parts. The extreme height of the vertical screw is necessary in order that free flowing breading may be directed from chute 19 to a central point in the hopper 13 for proper distribution to the product belt. This machine will not circulate flour breadings. FIGS. 6, 7 show the movable half 32 of the vertical screw housing and the ten vertical bends necessary to form it. FIGS. 8, 9, 10, 11 show the relationship between fixed housing 20 and movable housing 32. It must be understood that proper relationship is sometimes difficult to obtain due to distortions caused by welding, especially in a vertical screw as long as six feet. The side view shown in FIG. 1 indicates the presence of other complexities of form which are not numbered.
The second typical breading machine is described and pictured in U.S. Pat. No. 3,647,189--Johnson. FIGS. 3, 4, 9, 12 and 13 thereof show the complex configuration of the hopper 36, which again consists of multiple planes at various angles, and contains considerable mechanism for directing breading flow. The vertical screw housing 33 as seen in FIGS. 3 and 13, being placed at an acute angle with a horizontal plane, includes sheet metal shapes at both ends which are expensive to make and difficult to hold to dimensions. FIG. 3 illustrates the complexity of the drive for this machine, wherein the vertical screw 32, the hopper screw 43, the feeding device 56, the spreader screw 48, the discharge conveyor drive shaft 75 and the main drive pulley 49a for product belt 49 all must be power driven. FIG. 16 is a plan view of a level discharge conveyor with an open mesh conveyor belt. This type conveyor is used when free flowing breading is the coating material, because excess free flowing breading can be blown off the product by the arrangement of air compressor 93 and blower pipe 85 as seen in FIGS. 1 and 20. However, when flour type breading is the coating material, the excess usually cannot be blown off the product due to dust generation. Products coated with flour must be flipped over to remove excess breading, as illustrated in FIG. 24. It can be seen that if the owner of a breading machine of this type desires to use both flour and free flowing breadings, he may require two different discharge conveyors for the same machine. Even though the machine of U.S. Pat. No. 3,647,189 will circulate both free flowing and flour breadings, there are some flour breadings which require still further stirring and/or vibrating mechanisms in the hopper in order to correctly discharge the flour breading.
It may be readily understood that even though currently available breading machines can perform adequately while utilizing different styles of breading material, they can be quite costly due to complexity of form and mechanism. It might also be noted that complexity of form can make complete cleaning difficult due to the odd shapes of compound angles and the multiplicity of moving parts. Furthermore, the multiplicity and complexity of the moving parts of such breading machines almost guarantees high maintenance costs.